Dynamical magnetic breakdown and quantum oscillations from hot spot scattering

TL;DR

This paper introduces a semiclassical theory where bosonic fluctuations cause dynamical magnetic breakdown, leading to quantum oscillations that reveal Fermi surface reconstructions without static order, offering a new way to probe quantum critical metals.

Contribution

It develops a novel semiclassical framework for dynamical magnetic breakdown driven by bosonic fluctuations, explaining quantum oscillations without static density wave order.

Findings

Reconstructed quantum oscillation frequencies can occur without static order.

Tunneling probabilities depend on bosonic excitation populations.

Oscillation amplitudes deviate from Lifshitz-Kosevich behavior due to dynamical effects.

Abstract

Quantum oscillations (QO) are a well-established probe of Fermi-surface (FS) geometry and in the presence of long-range density wave order can display new QO frequencies from reconstructed FS pockets. We show that such reconstructed frequencies can arise even in the absence of long-range density order. Considering electrons coupled to a fluctuating bosonic mode that scatters quasiparticles between sharp hot spots on the FS, we develop a semiclassical theory in which the interaction generates time-dependent tunneling processes analogous to magnetic breakdown. This dynamical magnetic breakdown produces new semiclassical orbits corresponding to reconstructed FS areas despite the absence of static order. Because tunneling probabilities depend on the thermal population of bosonic excitations, the resulting oscillation amplitudes exhibit characteristic deviations from standard Lifshitz-Kosevich behavior. Our results provide a mechanism to probe bosonic fluctuations in quantum critical metals and provide a framework for dynamical magnetic breakdown.